The present invention relates to improvements in plastic saddles for bicycles, and more particularly to improvements in a saddle comprising a saddle base and strip-like support members integral therewith to support the base.
Saddles are mounted on the seat post of bicycle approximately in horizontal position. Plastic saddles have recently been introduced into use which comprise a saddle base and a pair of strip-like support members for supporting the base, both the base and support members being made or a rigid plastic material.
Such plastic saddles are grouped into two types: those made by molding the saddle base and the pair of support members separately and assembling them together with bolts and nuts, and those made by molding the saddle base and the support members integrally. Each of these types has its inherent advantages and disadvantages. As disclosed by the present inventor in U.S. Pat. No. 3,758,154, the saddle of the former type has the advantages that the saddle base and the pair of support members are easily and accurately moldable each in accordance with its function and that the molding procedure does not require much skill. However, because the pair of strip-like support members are fastened to the rear surface of the saddle base with screws, the saddle necessitates an increased number of assembling steps, the fastened portions are prone to loosening when subjected to shaking and the exposed fastening members are unsightly and reduce the commercial value. On the other hand, the saddle of the latter type in which the strip-like support members are integral with the saddle base has the advantages of eliminating the necessity of fastening them together, reducing the number of assembling steps and increasing the commercial value, whereas the saddle of this type requires skill for molding since the saddle base and support members have different functions and are therefore different in shape. However, with great improvements in molding technique in recent years, the latter integral type is advantageous for mass production.
With either of the types described, there is a common problem. The arch-shaped strip-like support members integral with or fastened to the rear surface of the saddle base are deformed in directions away from each other by the load of the rider on the saddle or due to shakes during cycling and, during years of use, the deformation leads to fatigue of the material, reducing the durability of the saddle. Although the prior art described employs a plate for interconnecting the rear portions of the pair of the support members to prevent deformation or deflection, with the plate alone it is still difficult to fully assure the desired function.
Because of the particular properties of the material, plastic saddles possess an ability to absorb shaking. Accordingly, the large distance between the abutments of the support members on the saddle base, i.e. the long span involved in the arch-shaped support members of the prior art, permits marked flexure of the saddle base, imparting an excessive shake absorbing ability to the saddle base. Consequently, there arises the necessity of providing reinforcing longitudinal and transverse ribs on the rear surface of the base to reduce the commercial value.
Saddles further include a shock-absorbing elastic member adhered to the top of the base and saddle cover covering the elastic member to provide a saddle top. As disclosed in the aforesaid prior art, the conventional saddle cover is fastened to the saddle base by a suitable number of L-shaped pawl members attached to the base. The saddle cover is provided with a drawable iron wire. After the periphery of the saddle cover is folded over the periphery of the saddle base, the iron wire is pulled, and the pawl members are bent over the periphery of the cover to clamp the cover. Thus the cover must be fitted over the base entirely by manual work, whilst depending on the degree to which the iron wire is pulled, the opposite sides of the cover at the rear portion of the saddle may possibly be wrinkled, seriously impairing the commercial value of the saddle.